1987 LJ70 frame swap + off road mods build thread (2 Viewers)

[Gubbtratt1]

Temporarily put the front back together to see how everything fits together. Seems pretty perfect to me.

I had planned to cut out the lower spring mounts from 4mm plate today, but the weather was a bit too unreliable so I'll do it tomorrow instead.

The Land Rover air springs have a pretty maintenance friendly mounting system. You put them on the axle, rotate a quarter turn, attach the air hose, extend them to the frame, and fasten with two clips. I'll have to make the top mounts a bit more complicated to fit the LJ frame though.

 

[Gubbtratt1]

I tried to do some oxy acetylene cutting today. It went very well for the first 5 centimeters, after that I noticed a flame where there shouldn't be a flame.

I have no idea what might have caused the damage, but it caused an acetylene leak that was apparently close enough to the nozzle to catch fire. The plan now is to get either a 25mm hole saw or a Parkside plasma cutter.

I finally got a brake drum off. The springs are more than strong enough to keep the brakes from dragging.

Now bleeding is the only concern. If it's impossible with the cylinder standing up I could replace the last bit of line with a hose and unbolt the cylinder when bleeding. A bit extra work to remove the wheel, drum, shoes and two bolts, but it should make up for not having to hammer the lever straight every time I go off road several times over.

 

[Gubbtratt1]

I also put some thoughts to the shocks. The original ones are too short and aftermarket ones are too expensive, so I've decided to go with Mercedes 508 shocks. They have 24.5cm of travel and costs about 60€ each.

The only problem is that they don't have the same bushings. All the front and the rear left top bushing is a completely different design, so for those I'll have to weld on bolts to the shocks, but for the rest I have three options.

From left to right:
1. Cut off the eyes from the original shocks and weld them onto the Merc shocks. Use stock bushings.
2. Cut down the stock bushings to fit the Merc shock eyes.
3. Press out the metal center from the Merc bushings and either slightly bore out the hole or hammer them onto the axle and frame mounts. The mounts on the car are the same diameter as the metal centers.

Opinions?

 

[Gubbtratt1]

Fun fact: Range Rover Classic shock bushings are identical to Toyota LJ70 ones. I'll go the route of welding on new eyes and using stock (although made for a Rover) bushings. I tried welding on a bolt today, and it went very well.

Seems like I accidentally took all pictures in vertical 16:9 instead of horizontal 4:3 as I usually do. A lot of unnecessary scrolling, especially if you're on a PC.

Anyways, I also sketched up the front suspension in FreeCAD as I did with the rear suspension a while ago.

I did it to figure out if I need to add spacers to the springs or to the shocks. Turns out neither, at full articulation the lengths at the compressed side are within 4mm of perfection.

In my quest to get as much suspension travel as possible I've also achieved a lot of theoretical articulation. I put together some numbers in a chart and ran them through a ramp travel index calculator:

I don't know how much sense it makes when you don't know Swedish and isn't the one who made it. Ask if you're curious, I started explaining each one but that would've ended up long enough to qualify as a novel.

 

[AirheadNut]

I would caution against modifying replaceable parts like shocks, and recommend instead modifying the shock mounts if possible. One of the things I have been battling on my swap project as I rack up the miles is needing to work on or replace parts that I had to modify the first time around. Every time one of those items has to be replaced you'll have to modify the new ones too, whereas if your permanent parts (like shock mounts/frame members) are modified instead you can simply swap the parts out like you would on a stock vehicle. More work up front, but much nicer for the future.

 

[Gubbtratt1]

I would caution against modifying replaceable parts like shocks, and recommend instead modifying the shock mounts if possible. One of the things I have been battling on my swap project as I rack up the miles is needing to work on or replace parts that I had to modify the first time around. Every time one of those items has to be replaced you'll have to modify the new ones too, whereas if your permanent parts (like shock mounts/frame members) are modified instead you can simply swap the parts out like you would on a stock vehicle. More work up front, but much nicer for the future.

I've considered the same, but I have no idea if the Merc shocks is the permanent solution. They might be way too soft. If that's the case I wouldn't want to have the frame and axles modified to fit parts that give a terrible ride and won't pass inspection.